<!DOCTYPE html>
<html>
<head>
<title>margin-trim: block-container-block-start-001</title>
<link rel="author" title="Sammy Gill" href="mailto:sammy.gill@apple.com">
<link rel="help" href="https://drafts.csswg.org/css-box-4/#margin-trim-block">
<link rel="match" href="/css/reference/ref-filled-green-100px-square-only.html">
<meta name="assert" content="block-start should trim block start margin for block-level first child">
<style>
.container {
    background-color: green;
    width: min-content;
    margin-trim: block-start;
}
.outer {
    background-color: green;
    width: 100px;
    height: 50px;
}
.child {
    width: 100px;
    margin-top: 50px;
    height: 50px;
}
</style>
</head>
<body>
    <p>Test passes if there is a filled green square.</p>
    <div class="outer"></div>
    <div class="container">
        <div class="child"></div>
    </div>
</body>
</html>
